Sheet material is used in a variety of ways in assorted types of construction. For example, various widths of sheeting are used in building construction requiring siding, soffit, facia board cover, flashing and the like. In most installations these materials are cut with power saws to expedite installation. However, there are many job sites where power is not available, the installer then has to resort to a hacksaw or tin snips to hand cut materials for installation on the building. The sheet materials may be of either aluminum or plastic and for larger widths of a foot or greater, it can become very difficult to cut by hand. Furthermore, in using standard hand tools to cut the sheeting material, the shape of the material is altered by the use of saws, tin snips or the like so that when the materials are installed they may not interfit properly.
There are sheeting material cutters available, however, they are generally of a construction which is very heavy and therefore difficult to move from job site to job site. Furthermore, the cutters are designed to shear a particular shape of siding material or the like and are therefore not readily adaptable to cut a variety of sheet materials on any one job site. For example, very large and heavy corrugated sheet metal cutters are disclosed in U.S. Pat. Nos. 363,524 and 2,582,933. These patents involve the use of arcuate shaped shear which passes between spaced-apart shear dies which are mounted in place on support blocks for the base of a cutter. The shear dies are rigidly mounted and are set on adjustable beds to provide the desired degree of spacing between the shear dies relative to the shear blade.
A complex sheet metal cutting shear is disclosed in U.S. Pat. No. 2,355,320, the system involves the use of a complex linkage to increase the leverage applied to the shear blade as it cuts the sheet metal. Although the linkage requires less effort during the cutting operation, the linkage adds considerably to the complexity of the design and the weight of the cutter so that it is not easily transported. The shear dies are mounted on the base of the cutter with adjustable stops along the upper edges of the shear dies to establish the desired spacing between the die edges.
Similarly relatively complex cutters are disclosed in U.S. Pat. Nos. 3,714,856 and 4,130,037 for shearing various shapes of sheet materials. The patent to Hall et al like Nebel No. 2,355,320 has a complex linkage mechanism to maintain a desired angular relationship of the shear blade relative to the material being cut. Removable inserts are provided on the shear dies to compensate for sheet materials having stepped portions, to thereby provide support during the cutting operation. However, the major workable portions of the shear dies are fixed in shape and cannot be removed, nor can the spacing between them be precisely adjusted. However, such spacing is not as critical because of the elaborate linkage mechanism which supplies plenty of force in shearing the material. In Matthews U.S. Pat. No. 4,130,037, the shear blade includes a pointed portion which enters the material first and then sections of the blade to each side of the pointed section cuts the remainder of the U-shaped channel. The shear blade has a knife edge which passes through a slot defined by opposing surfaces of a bed which supports the U-shaped channel. Instead of shearing the material, the blade edge actually cuts the material, because of the general U-shape thereof. The one edge of the shear die which abuts the knife edge of the blade, is fixed so that replacement of the entire cutter is required once the edge of the slot becomes worn.